What behavior may indicate that a pet is suffering from parasites?

Constant scratching or rubbing against surfaces is a significant behavior that may indicate a pet is suffering from parasites, particularly external parasites such as fleas, ticks, or mites. These parasites can cause itching and discomfort, prompting the pet to scratch or rub their skin in an attempt to relieve the irritation. This behavior often becomes pronounced and noticeable to pet owners, leading them to investigate potential causes for their pet's distress.

In contrast, increased playfulness, frequent barking, and refusal to go outside do not specifically correlate with a parasitic infection. While changes in behavior can suggest health issues, in the case of parasite infestations, the most direct and common sign is the physical irritation that leads to constant scratching or rubbing. This makes it a more accurate indicator of possible parasite-related issues in pets.